


Hat Tricks

by FrostedFlame (PinkOrchid)



Category: Sherlock (TV)
Genre: Drug Addiction, Emotional Infidelity, F/M, M/M, Multi, Polyamory Negotiations, Sherlock Holmes and Drug Use, The Deerstalker Hat
Language: English
Status: Completed
Published: 2016-01-03
Updated: 2016-08-31
Packaged: 2018-05-11 06:40:15
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 12
Words: 13,664
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5617195
Author URL: https://archiveofourown.org/users/PinkOrchid/pseuds/FrostedFlame
Summary: <blockquote class="userstuff">
              <p>Set just after the plane lands in the Christmas Special (The Abominable Bride). All is not well in the Watson/Morstan marriage. Mary shows how far she'll go to keep her husband. However a misunderstanding drives John away, and Mary and Sherlock must work together to guide him home again.</p>
            </blockquote>





	1. How Sherlock Came to Stay in Suburbia

**Summary for the Chapter:**

> This chapter has been modified since it was originally published. On re-reading, I felt it was too weighty in comparison to the chapters that follow, too big a jump in tone. It would be unlikely that after an OD-type episode Sherlock would be quite as ok-again as I need him to be for what follows. So I've altered timeline (slightly). There are a lot of fics popping up that deal with the dark aftermath of drugged!Sherlock amazingly, but that didn't fit quite here.

After the plane touched down, after Sherlock emerged from the drug-induced fog of his mind palace, after John yet again set aside his righteous fury at Sherlock for doing something so stupidly dangerous, it was inevitable that Mycroft would step in to manage the fallout from the List and everything it represented. Sherlock was whisked away to a facility (or a locked room in one of Mycroft's mansions, John couldn't be sure) to manage the come-down, detox and withdrawals. John desperately fought to join him, but in the end it was Sherlock himself who had begged him to stay away. That stung. He could understand it in a way. Sherlock, always so controlled, keeping the image pristine, would not want John to see him in that state. Nonetheless, John wished Sherlock would let him be there, would trust him not to think worse of the man for being human. But as usual with Sherlock, he couldn't refuse a request so earnestly made. So, for John, there was finally nothing more to do but wait.

Mycroft called once Sherlock was over the worst and ready to be released back into the world. At John's request, he sent a car. Mary - of course - came too. Sherlock looked miserable and somehow  _smaller_  sitting beside the hospital-style bed, and John knew right then there was no way he could leave Sherlock alone in the weeks to come. He was obviously not in imminent danger health-wise (though John wondered how much more of this his body would take, really). But who could tell what he'd do if left alone in Baker Street now? John looked at Mary, a question in his eyes, but in reality even if she'd said no he would have gone with Sherlock anyway. She probably knew that too.

"Why not come back with us, Sherlock?" she asked, and her voice was almost tender - after all, she cared about him too, in her own way.

John could see why she had suggested it - as heavily pregnant as she was, it wouldn't be comfortable for her to be camping out in Baker street. And even John was honest enough to admit that were he to return to Baker Street now, he might not come back for some time. (The 'if at all' went unthought and unspoken, but it was drifting at the edges of his subconscious nonetheless). So, if Mary was to keep John close, then it made sense that Sherlock came to their house in the suburbs instead. She knew full well John would not leave Sherlock in this state. At least this way she could be part of whatever happened, first hand. She was never one to sit at home and wait, after all.

Sherlock looked back at her, unblinking. His gaze was part curious, part suspicious. She held her breath for a second, until finally he nodded, indifferent mask firmly fixed back in place.

"Alright," he said.

John helped Sherlock out to the ever-present black car, noticing how shaky the man was on his feet. He mentally kicked himself for the hundreth time since the plane landed. How could he not have noticed? 'Sherlock is a girl's name'. How did he not realise the great git was high? He was a doctor for God's sake. He tried not to think about how many other times Sherlock had 'seemed' sober when he may have been high as a kite. How long had it been going on right under his nose? It was not a pleasant thing to contemplate. And then there was the - don't think about it now - question of whether he was trying to kill himself before arriving in Serbia, or was it just to ease the departure, a last blast before his mission began? Nobody was buying the 'I had to go deep into my Mind Palace to solve the Moriarity problem' excuse. He had to have taken the drugs long before the video that triggered his return had aired.

John sighed to himself. He loved Sherlock. He really did. He was so relieved to finally have Sherlock here, where he could keep a proper eye on him. It wasn't Baker Street, but it was better than the exile from his side that had been enforced for the past few weeks. That had been excruciating. He didn't know how they would manage a stroppy, withdrawn Sherlock. But they would. They just had to. John clenched his fists at the thought of how easy it would have been to have lost Sherlock again. The idiotic things the genius did really made it hard sometimes to hold his tongue. He decided the 'tough love' speech could wait, and focussed instead on settling his friend into the guest room (though he was sure the man would probably not sleep that much in any case) and set about making tea. 

 


	2. The Hat's Debut

**Summary for the Chapter:**

> Oh the hat, the hat.. wherefore art thou hatkins? Seriously. There's a point to the hat. Really.

Sherlock's 'rehabilitation' was hard on all of them, but by the end of the week he seemed to be making progress. Only John's steady presence kept the worst of the boredom at bay. Only John Watson kept him right. He would do this - had done a lot more - for John. He still ached for a hit and was weak and shaky as a new-born foal. But he was back to his more normal self and was following his doctor's orders admirably - well, considering! They still watched him like a baby, though. They seemed to think he couldn't be trusted on his own for any length, so they were taking turns to 'occupy' him (really it was just glorified babysitting, something he would never have accepted from anyone other than John and his wife, truth be told). 

Sherlock threw himself onto the sofa, sighing. It was Mary's turn right now and she was reading him an article on particle physics out loud. He wasn't sure why either of them might be interested in it, and planned to delete the information forthwith, but he indulged her anyway. Irritably, he reached beneath the sofa cushion to investigate that lumpy bit under his left hip. His hand met something cloth which had evidently been balled up and stuffed hastily under the seat. He pulled it out, his face a mixture of disgust and surprise when he recognised the item dangling from his elegant fingers. 

"Now what's this, then, Mrs Watson? A 'Sherlock Holmes' hat? What is that doing here? T'isn't even mine!"

Mary giggled - Sherlock liked it when Mary giggled. What was it with the Watsons and inappropriate laughter that always made him feel so warm?

"Oh God, don't - put it away! You can't let on you've seen it."

"Why, Mary? What possible purpose could it serve under a sofa cushion? I sense a mystery!"

"Seriously, Sherlock - put it back!"

"But why is it even here, Mary, that's the question."

"Shh - don't let John know you've found it!"

"Why not? Sounds like a puzzle, and you know how I love a good puzzle. Anyway, if you don't tell me I'll only deduce it! The game is on! Really Mary, you can't expect me to just - "

He broke off as John stormed in and attempted to snatch the hat out of Sherlock's hands. Drug addict or not, his reflexes were excellent, he jumped up just in time and dangled it ever so slightly out of reach of John's shorter arms. A puzzle -and something John didn't want him to see. How could he resist? He grinned at his friend, a clear invitation to play. It had been a while since he had felt so light-hearted. 

However, even when light-heartedly teasing, he could read John Watson. It took less than 2 seconds for him to realise that the man was absolutely livid. And embarrassed, no- not embarrassed, more like ashamed. Interesting!

"Give. It. Back," John growled. "NOW!"

Sherlock lowered his arm and allowed John to snatch the offending item from his grasp. 

"It's just a hat, John," he said. "Doesn't mean anything-"

John cut him off with a hand motion, turning to Mary instead. 

"How could you?" he hissed. "You promised! You promised you'd throw it away."

His voice had a strangled quality. He had gone a rather worrying shade of purple. It was clear John Watson was very angry indeed. Mary's face had fallen, she looked - also ashamed. Horrified. And a little guilty too. 

"But - I just forgot - I thought - "

"You bloody knew how I felt about this. You promised you'd get rid of it. And now you're laughing about it - with him? Go on then - have a laugh. Pathetic John Watson. Go on - both of you! Fucking hilarious. I get it. I really do."

His eyes were flashing, he was a tiny ball of compact fury let loose. Sherlock couldn't stop himself from thinking how marvellous he looked when spitting fire like this. He knew John was serious. Not good to be thinking about how sexy he was like this, how magnificent. Nope. Not at all. 

"John!" Mary shouted back, trying to stop him before he lost it. "Don't - it's not like that. We -"

John didn't wait for her to finish. He stalked out of the room, grabbing his jacket in the hall, and kept on stalking right out of the house, slamming the front door behind him. Sherlock and Mary ran to the window overlooking the street. They watched as John pulled open the large communal bin in front of the building. He positively rammed the hat inside, throwing the lid closed again with a resounding clang. Instead of coming back into the house, he stormed off down the street. 

This was most definitely 'not good', but Sherlock had no idea what he'd just done wrong. He looked to Mary, a mute plea written across his face. 

"Mary," he whispered. "Why is John so upset about a stupid hat? What did I do?"


	3. Under your Hat

**Summary for the Chapter:**

> The mystery of the Hat is revealed

**Notes for the Chapter:**

> Ok I know I thought I could do this entire fic in one sitting - but - it's getting late. Will have to resume tomorrow!

Sherlock really needed to figure out why John had been so angry. His question to Mary quivered between them. _Why?_

Mary looked down at her hands instead of answering. She was looking a little pale, clearly upset. This couldn't be good for the baby. Sherlock wasn't sure if he should push for an answer or send her to lie down. But he was never one to molly-coddle the witness. And if something was wrong with John - well, he had to know. He had a right to know. This was John. His John. His best friend. 

"Mary?" he nudged once more. This was as close to gentle as he could get, when it came to interrogations. 

"It's - it's not your fault, Sherlock. It's mine. It's my own stupid, stupid fault."

"Elaborate." The single word from Sherlock was quite clearly a demand, not a question. 

Mary looked away from him, out the window. She seemed to be struggling with whether or not to tell him what was going on. Finally, she sighed, seeming to come to a conclusion. 

"Things - things haven't been easy since we reunited at Christmas, Sherlock. John still doesn't trust me. I know he has reason. But - we're not right. We barely talk. We're not close any more, not like we were before." 

_Before you shot me_ , he thought. But refrained from saying. Some things were best left to sub-text after all. 

"I see. But what has that to do with the hat, Mary?"

"John and I - we haven't. Well, you know. Since he came back."

"Haven't what?"

Mary blushed crimson but raised her eyes to Sherlock's, almost as an act of defiance. 

"Haven't - you know. Had - relations. I mean. Oh God. I mean - we haven't slept together since before this whole thing with Magnussen kicked off!"

"What? Not - not once? But - he's so highly sexed. He must have - I mean - you're reconciled, Mary. He said he's forgiven you."

"Yes,"she muttered dourly. "Tell that to his penis, why don't you."

Sherlock was not one to blush easily but now it was his turn to look away as the tips of his ears grew warm. The silence dragged. It was not companionable. It was bloody awkward. Sherlock cleared his throat.

"Much as I commiserate," (he didn't - he really didn't - somehow the news of the lack of sexual activity in the Watson's chambers filled him with an emotion poles apart from sorrow, but he refused to think of that now) "I fail to see how it relates to - what just happened here today."

Sherlock was caught between a sense of revulsion - he didn't need to hear the details - and a strange kind of fascination - _he really wanted to hear the details_. This was - this was John. John's sex life. John's - his - penis. John's penis interested him more than he was willing to admit. He swallowed. How could he not be interested, in spite of himself. Even John was never as forthcoming with Sherlock on the subject of his sex life. 

"He insists it has nothing to do with forgiving me," Mary continued. "At first he said it was because of the baby, but that hadn't bothered him before. Then he told me he 'just isn't interested' in, well, in 'that kind of thing' right now. Says he can't pretend. That it'll most likely come back when it's ready. Have you any idea how hurtful that is? If he's really forgiven me - I mean - he should want me, right? I'm his wife for crying out loud!"

She was starting to stray off topic. Need to focus, get to the point. 

"And the hat, Mary? What has this to do with the hat?" 

He really couldn't see a connection, but - there had to be one, why else was she telling him all this. Oh God - she shouldn't be telling him this, should she?

"The hat was - it was partly a joke really. Oh God. The hat was - it's silly. I bought it as a bit of fun. You know."

Sherlock just stared at her, his special thousand-yards stare. He evidently didn't know. Mary swallowed. She was just going to have to say it, wasn't she?

"I wore it, Sherlock. I wore the hat."

Blinky blink blink.

"JUST the hat. I mean - nothing else. I put on the hat. And waited for him to get home, on the sofa. Naked. Apart from the hat."

Mary was looking at her hands again, her face flushed. 

"Why? Why would you do that? What possible reason could you have to-"

"God, do you have to be so - isn't it obvious?" Mary's voice was rising, frustration and anger vying in her tone. "Christ, Sherlock - I was trying to - I wanted to get him in the mood, alright? I was so desperate to reconnect with him that I wore your bloody hat to try to make him want me too!"

Sherlock's eyes shot to her face. Had he heard that right?

"Too?" he said, his voice suspiciously shaky. 

Mary laughed, bitterly. "Don't play the innocent with me. You must know how he feels about you. You've always known. You just don't 'do' relationships, sex, any of it. Sentiment is a defect. Need I go on."

"Mary - I don't - I really don't know what you mean. John doesn't - we never-"

"If John had not thought you dead and buried, I would never have stood a chance. I know that. Oh yes, he loves me. But not - I repeat not - like he always loved you."

All the air seemed to have left the room. Sherlock couldn't breathe. John. John - loved? - him.. it - it didn't make any sense. 

"So I wore the damned hat," Mary continued, as if Sherlock were not about to expire from lack of oxygen just two feet away. "I wanted to get a reaction, maybe to remind him of you, to turn him on perhaps. Or just to get him talking about you, to finally admit that there are three people in this ruddy marriage and always have been. I knew from the very first date that you would always be in the middle, Sherlock, but - you were dead. I could have handled a ghost. A living third wheel - that's a little harder to accommodate."

Mary paused - but Sherlock was in no condition to reply.

"Hell, I'm a pragmatist. I'm not too proud to do what it takes to salvage this marriage. I thought if we could at least talk about you, it might have lit a spark for us, helped rekindle things. Given John an outlet for all that unresolved tension. It might have been a way back in. And triggering an automatic reaction to an external stimulus, something that symbolised the object of his desire - it was a good theory."

Suddenly comprehension dawned. "Using what you considered a positive association to an object. Clever. Like Pavlov's dog," he muttered. "Only - John's not a dog, Mary. And - my hat is not - it couldn't ever be considered desirable. Ever."

"It wasn't really the hat, Sherlock. It was you. Always you."

"But - what could you hope to achieve by that? I take it that the matter did not go down well with John?"

"No - he went crazy. I thought if that was finally out in the open between us, we could talk about it. He'd know I accepted how he feels about you. That there was a place for it between us. That he didn't have to hide. But he acted like I had accused him of cheating. I swore I'd get rid of the hat and we'd never talk about it again. Only - with everything that happened, I just forgot. And now he thinks I humiliated him - that I was laughing about it - with you."

"Oh no," Sherlock groaned, sinking his head into his hands. "When he came in, I was laughing too. He'll never forgive us. He has such awful pride. "

Mary's distress was palpable. Sherlock looked over at her, a twinge of affection running through him. Suddenly, the image of her, naked, on the sofa, wearing a tweed deerstalker hat was so vivid in his mind that he had to shake his head to clear it. 

"Mary," he said. "This really isn't my area. What are we going to do?"


	4. Meeting of Minds

**Summary for the Chapter:**

> Sherlock and Mary come to a new understanding..

"I don't know, Sherlock. I don't know what to do any more."

She looked despondent, like this was something she'd been thinking about for a while, to no avail. 

"Tell me this - do you love him? Truly love him?"

"More than anything."

"Then we we fix it, Mary," he said, more firmly than he was feeling. "We're two intelligent, driven people. We are not afraid to do what needs to be done. Between us - we can fix it."

"Intelligent? That's high praise coming from you," said Mary with a wry smile. "I thought we were all idiots."

"Mary, you and I are more alike than you might think."

"Yes, that's why John chose us, after all."

"How long have you known?" Sherlock asked quietly, for once glad to not have to hide this secret that had been pressing on him for so long. It was a relief to be able to speak openly about it, even if it was - almost unbelievably - to John's own wife. 

"That my husband was in love with someone else? For as long as I've known him, Sherlock. It was always a package deal. You, on the other hand, well - I guessed, but - with how you are, I couldn't be sure. I suspected, from the first time I met you in that restaurant. But - no proof. You were good at hiding it. Too good. Even John doesn't know."

"I've worked very hard to make sure he doesn't, Mary."

"Why? Why would you deny it?"

Sherlock shrugged. "Timing, mostly. At the start - I didn't  _want_ to love him, to love anyone. I had put sentiment aside long ago. I fought it. And I wasn't sure - I knew he admired me, cared for me. But love? How could I be so arrogant? I didn't want to risk his friendship. It seemed all risk and no hope of reward. Then came Moriarty and all the madness that ensued. And there was no time, it was too dangerous. It would be too easy for someone to use him against me. It would put him in danger."

Mary nodded. "Leverage," she said, softly. It was true. She would have used him too, had she been working for Sherlock's enemies. Make use of any weakness, the soft underbelly hanging low.

"Then I was, well, away. For longer than I thought. Two whole years, with only the thought of John to bind me to life. By the time I got back, he had found you." He raised his eyes to her now, so much sorrow in the icy green. "I could see he loved you. I couldn't, wouldn't ruin that for him. How could I be so cruel? Knowing you can give him what I can't. Normality."

"Normality?" Mary asked, incredulously. "You think I can give him 'normal'? I'm a retired assassin, I've killed people in cold blood. I still could. Would if I had to. You think I can offer picket fences? Really?"

"More than I can. You're - you may have the capability to kill, Mary, the same facility with lies, manipulation that I do. But - you're better at blending in. You can fake it, look around you! And I know you love him. There was never a question in that regard."

"But you love him too, don't you. And you'll never quite be able to let him go."

"I let go _enough_. I stepped back, I pushed him away. I planned your wedding, Mary. Do you forget that? I realised, as soon as I got back, that you can give him a regular life, or a close approximation. And I could provide just enough spice on the side to keep him from getting bored."

Mary laughed softly at that. "Yes, we both know our soldier needs a little danger to keep him right."

"And then there's -" he gestured at her belly. "The baby. It's the one thing I couldn't give him. I know he wants that. He deserves it. And how would a child ever fit in with a life at my side? No - I had to let him go, but not completely. I'm a selfish man, at heart. But I want him to be happy and I calculated that his best chance of that is with you. With someone who can love him openly and without - without censure. He suffers so much derision for simply being my friend. I couldn't - I couldn't ask that. Not of John. I love him too much to ask that."

"But you forgot one element in your equation, Sherlock."

He looked at her, a puzzled frown creasing his brow. 

"What - what did I forget?"

"You forgot about John. You forgot to factor in _his_ feelings. That he loves you too. That he wouldn't let you go, either. If it came to it - I have no doubt that he would choose you over me, every time." Her voice sounded matter-of-fact. Like she'd long ago made her peace with this. 

Sherlock gulped. He stared at Mary, slightly horrified. It was true! He had forgotten about John in all this. Wasn't that what John always complained about, in the end? Being left out, not consulted about things that concerned him? Being 'handled' and manipulated and -  _oh God. I've done it again, haven't I?_   His face fell.  

"Oh Sherlock. There's always something." 

She smiled, not without affection. They held each others eyes, long and hard. 

"So - what do we do now?" he asked.

"Well, I _was_ all out of ideas," Mary said. 

"Was? Past tense?"

"There is one thing that occurs to me. But you may not like it."

"Oh?" He wasn't sure he liked the sound of that. 

"Sherlock - let me ask you something." Mary paused, biting her lip. It was make or break really. They'd said so much already. Why stop now? "Have you ever actually  _had_ sex?"

Sherlock's head snapped up. This was something even  _John_ hadn't dared to ask. Trust Mary to cut straight to the chase. They really were quite similar, weren't they?

"Yes, a long time ago," he answered, reluctantly. 

"Was it with a man? Or a woman?"

"Both, if you must know. I - experimented. In college. It was - not unpleasant. But hardly satisfying enough to miss it terribly ever since."

"So - you enjoyed it, even a little?" Mary seemed relieved. Why would she be relieved? "Is - forgive me, but I need to ask - is sex something you would consider with John, if you were to further your relationship with him? Or - would you by preference stay platonic?"

"Ah. I see what you're asking. No, I am not actually asexual. Just not highly sexed, and used to denying my transport in furtherance of my mind. So to answer your question - yes. Yes. If I had been able to 'be with' John, it would most definitely have had a sexual element."

"And - again, this may seem intrusive, but, when you were experimenting - did you find you had a preference? In the gender of your partner I mean," she asked, gently. She was good at gentle. 

"How is that in any way relevant?" he asked, before realisation dawned. "Oh. Oh I see. You mean-"

"Yes. If you might have an interest in that."

"In you, you mean."

"Bluntly put - but yes."

Sherlock eyes narrowed as he watched her. Interesting. He hadn't been surprised like this in such a long time. 

"Why? Am I to believe you find me - desirable in that way?"

"You are undoubtedly aware of your looks, Sherlock. You know you are handsome. God knows you use it often enough to get what you want."

"That doesn't answer the question."

"I don't desire you in the way that I desire John, no. But I do find you attractive. And while I don't love you, I am fond of you nonetheless. I've been with people for far less." 

"What exactly are you suggesting? How would us having  _sex_ help anything?"

"What I'm suggesting - it is unconventional - but it could work. I'm suggesting that we - well, we share John. That we both love him. Together."

Hope flared unbidden in the dark recesses of his heart. Was she really offering what he thought she was? Or was this all a trick? Did she really mean that he could have John? Be with John?

"Like a time share?" he asked. "Like alternate weekends and every second Tuesday of the month?" He kept his eyes locked on Mary's face. She had very few tells, but he was starting to read a few. "Ah. No. You meant - together as in 'at the same time', didn't you? Interesting. Why?"

"Because John would never sleep with you without my permission. And even with it, he would struggle. He would feel guilty. Like he was cheating. On both of us. It's - just the way he is."

Sherlock knew she was right. Deep down, he knew. John would never cheat on Mary, and that he would regard any deepening of his relationship with Sherlock as cheating, regardless of 'permission' in advance. And given the baby, unless Mary were to do something really terrible ( _like shoot me?_ ) he wouldn't leave her now. No - she was right. If they were to do this, they'd have to do it together. And drag John along with them, somehow. 

He was beginning to feel he had vastly underestimated Mary. It wasn't an entirely unpleasant thought. 

 

 


	5. Sleep on It

**Summary for the Chapter:**

> John arrives back unexpectedly. He is understandably confused.

Sherlock narrowed his eyes and favoured Mary with one of his patented laser-focus stares. He noted, with satisfaction, that she held his gaze unwaveringly. Good. For what they were about to do, she would need to be able to hold her nerve. 

"Mary," he said, voice dipping slightly lower than his usual register.  "I have given it some consideration and I wish to take you up on your _proposition._ The only question is, how to broach it with the, ahh, other party involved." 

"I think between us we can come up with something. Though, in general with John, the truth is usually the best option. As I've found to my detriment." 

She paused momentarily, eyes flickering over Sherlock's face, assessing. 

"What about you, though?" she asked. "Is this really what you want?"

"You mean will I really be able to follow through with the sex-part, don't you? Call a spade a spade, Mary, for heaven's sake. If we're to get naked together in the near future, we shall have to be able to speak plainly about this kind of thing. I respond most favourably to bluntness in matters such as these, I think you'll find."

"Alright then," she smirked. "So - do you think you can shag me? Kiss me? Touch me? Or must we keep John firmly in the middle? I need to understand your boundaries before we start."

Sherlock sighed. This was a little tedious. But it would be worth it to finally be able to be with  _John_. Of that he had no doubt whatsoever. 

"I have no issue with any of that with  _him_. Rest assured of that. But I am also amenable to some interaction directly with you. I am open to both giving and receiving touches and light kisses - no tongue however. Oral is fine, as is penetration, though I would much prefer to be penetrated myself than to attempt to penetrate you. I am not sentimental. I do not require you to act  _lovingly_ towards me. I respect and like you and I think we will manage very well. While I would not have sought out sexual congress with you independently of this kind of arrangement, neither do you repel me - physically or mentally."

"Such glowing accolades, Sherlock. I can barely contain the blushes," Mary said wryly.

"I speak plainly but have no wish to hurt you, Mary. I rather like you, in fact. And your willingness to allow me access to your husband in this way is - rather amazing."

"I am not doing this out a misplaced sense of altruism, Sherlock. It's something I feel may help keep us together. I'd do anything to keep him. You know that."

There was a long silence as Sherlock thought about what this would mean. He had not lied to Mary, there had been - brief but nonetheless valid - experiences with women, and although he vastly preferred being with men, it had been enjoyable in its own way. His one concern was that these experiences had been some time ago. He was sorely out of practice. And he didn't want to ruin the mood by being awkward or finding things, well, difficult, on the night. Once again Mary surprised him.

"You are a little concerned that you may be out of practice, though," she said. 

Sherlock nodded. No need to go into detail, if she already understood. 

 "Why don't we practice, then?"

 "What?" Sherlock sputtered. He hoped he had mis-heard. "Surely not without John?"

"Oh Sherlock love, not like that. It's just - we may only have one shot at this with John. He'll likely spook easily. We will need to be decisive, show absolutely no hesitation. If we flinch, it might give him an excuse to change his mind. So you have to be comfortable from the start. If that means we have to practice, so be it. Besides, I didn't really mean you had to have sex with me right now. Just - get used to being physically close to me. Closer than you usually are. Perhaps without so many clothes on."

"Ah. Desensitisation. Yes. Excellent idea. Let's get going then."

And with that, Sherlock Holmes began to strip. Mary rolled her eyes but gamely joined in. Sherlock paused when he was down to his underwear, balancing awkwardly on one leg as he pulled off his socks. 

"Yes, let's leave underwear on for now," Mary said. "Why don't we get comfortable on the sofa? There's bound to be something on the telly. Oh and there's a blanket on the back of the sofa, keep out the chill."

It took a while, and there were moments that it was painfully awkward, especially considering Mary's pregnancy and resulting bump. But they ended up sitting quite closely, and engaging in what might - to the untrained eye - be termed 'snuggling'. The room was warm. The tv was mumbling in the background. It was surprisingly nice. Which might explain how they  _both_ ended up slipping into a peaceful sleep. 

A sleep that was rudely awakened by Captain John Watson of the fifth Northumberland Fusiliers who had arrived home in the small hours, hoping not to wake his wife. He was understandably astonished to find her and his best friend semi-naked under a blanket - and on his own bloody sofa, too. He took one look, sputtered his indignation, and did an about turn and stormed out - door slamming loudly in his wake. 

"What will we do now," asked Sherlock. This wasn't his area after all. 

"I doubt he'll be home again tonight. May as well get some sleep," Mary said, calmly. "He'll come round, don't you worry. He always does. Just - would have been better to have broken it to him a little less graphically, given him time to warm to the idea. You know?" 

Sherlock did know. John was best handled gently, doling out crumbs and allowing him to follow them to their natural conclusion. Try to force-feed him and he'd baulk. No, Mary was right, give him a day or so, then see how he was getting on. 

Sherlock was not a religious man. Nonetheless he found himself whispering a silent prayer. Please _God_ this would work out. He had never been so hopeful or so terrified in all his life. This had to work. _It just had to._

 

 

 

 

 

 

 

 


	6. Brotherly Advice

**Summary for the Chapter:**

> John comes round. Eventually.

Sherlock surfaced gradually from a surprisingly deep sleep. He felt comfortable and relaxed as he registered a pleasing sensation of warm skin against his unclothed chest.  _John_ his mind supplied. But when he opened his eyes he realised the owner of said skin was not John, but Mary. She was sleeping, so he felt obliged not to move just yet, for fear of waking her. The forced inactivity gave Sherlock time to think. He idly wondered how they would talk John around to their plan - assuming the man came home any time soon.  _Idiot_ , he thought. Probably out stewing somewhere still. Sherlock also took a moment to marvel at how good it felt to have Mary nestled against him on the sofa. He hadn't been  _held_ in a very long time. It was nice. Very nice. He could get used to it, actually. Mary felt soft and warm and - accepting of him. That fact alone gave him hope that their mad scheme might just work. 

But first, they would have to persuade John!

Beside him Mary stirred, then woke, with a stretch and a yawn. 

"That was nice," she said.

Sherlock hummed non-committally. 

"How did you find it?" she asked.

"It was rather more pleasant than I anticipated," he replied, "although I don't think I am feeling any kind of active desire for you. But - I do like the feel of your skin against me. I could - I could work with that. I like how soft you feel."

"Good, that's a start anyhow."

"What are we going to do about John? Should we try to ring him?"

"No - leave him be for now. He'll be back. He just needs a little time to work things out."

She stood and grabbed her discarded blouse.

"So - in the meantime - tea?"

Sherlock nodded and wondered if she was right about John coming round on his own. He reassured himself with the thought that Mary did know John better than most - she was his wife, after all. He just wished they'd had a chance to ask him about it, before he found them tangled in a scantily-clad heap. God only knew what he thought of them now. 

***

John knew exactly what he was thinking. He was so angry he felt he would explode.  _How could they? His best friend. His WIFE. First the humiliation of that bloody hat and now - betrayal._ He walked and walked and didn't stop until he was thoroughly lost. He didn't know how he was going to find his way back. He felt utterly alone. Of course, that's precisely when the sleek black car pulled up alongside. John fumed silently for about 2 minutes, then - being a very practical man - simply rolled his eyes and got into the car. Even putting up with Mycroft was preferable to the long walk home. 

"Mycroft."

"John"

Mycroft gave that minute movement of his head that probably signified a nod - or maybe just a nervous tic. John could never be sure.  

"To what do I owe the pleasure?" John asked, eyebrows raised alarmingly. Anyone who knew John generally took two steps back when he deployed the eyebrows, but Mycroft seemed unphased.

"How is my baby brother? I do hope he's not been making a nuisance of himself?"

The smug tone irritated John's fragile nerves, the way sandpaper would a wound.

"He's fine. Better than fine. He's bloody marvellous!"

"Hmmm. If you say so," Mycroft smirked.

"Why am I here? What did you want again?"

"Just passing by, thought to offer you a lift. Save your leg from over-exertion. After all, you're not getting any younger Doctor Watson, are you?"

"What's that supposed to mean," John practically snarled.

"Oh - nothing really. Only that - if you'll forgive me, opportunities to, ahh, have ones _cake_ and eat it, well, let's just say they don't come round very often. I'd advise you to go home and talk to your wife. And to my silly little brother. They may have erred in the execution, but I think you'll find their _logic_ is rather impeccable. They are, after all, startlingly alike. And alarmingly intelligent."

"What's that supposed to mean?" John hadn't calmed down fully, but he was definitely less angry now he had something to think about.

"Simply that you're about to be made an offer. You'd be wise not to let your emotions cloud your thinking, John. You're not exactly stupid, once you stop acting like a caveman. I think you'll rather regret if you pass up an opportunity just because you're angry at them. Remember - they don't feel things the way you do, not exactly.  But that doesn't mean that they don't feel at all."

John was confused. But he knew that Mycroft was the one person in the world who might know and understand Sherlock better than John. If it meant swallowing his pride and putting aside his anger long enough to listen - well, he could do that. But God, he hoped it wasn't what it looked like. If Mary and Sherlock were in love - it didn't bear thinking about. Losing one would mean heartbreak. Losing both - intollerable.

Mycroft instructed the driver to deliver John to his house in the suburbs. He didn't speak again the rest of the way, having delivered his message he would waste no further words in idle chit chat. He hoped the idiot Doctor would refrain from punching his brother, this time. Really - all that testosterone, can't be good for one. 

And on that note, he gave a brief nod to the by now visibly more relaxed army Doctor, and drove away. 


	7. Cake and Eat it

**Summary for the Chapter:**

> John makes his decision

John did not know precisely what he was expecting on returning home. But it most certainly was not this. Sherlock and Mary were sitting at the table in the kitchen, drinking tea and  _talking._ It was a perfectly normal scene on a perfectly normal day. Except it wasn't normal. Nothing about this whole thing was in any way  _normal._ John took a deep breath. And then another. And when that didn't seem to be working, took yet another again. 

Mary and Sherlock watched him, their eyes sharing an identical shade of appraisal. John felt pinned by those eyes. Like he had nowhere to run.  _Oh for God's Sake!_ he thought,  _Why am I the one who feels uncomfortable here? I'm not the one who was found - canoodling! - on the sofa with my husband's best bloody friend!_ John stopped himself with no little effort. He knew shouldn't continue that train of thought if he wanted to hear them out. He clenched and unclenched his fist. He continued to breathe. Deeply. It wasn't particularly helpful. 

Mary spoke first. 

"John," she said, managing to sound entirely normal. "I was hoping you'd be back sooner rather than later. You must be tired. And thirsty. Sit down, then. Have some tea."

John ground his teeth, afraid to say anything at all. 

"John," said Sherlock. "Don't be an idiot. Sit."

John sat, in spite of himself. He always was a sucker for that voice. He could never refuse Sherlock anything - for all his bluster to the contrary. He favored them both with his patented Captain Watson glare-of-death. But he knew they wouldn't take it seriously. Neither of them ever had before.

"Would someone mind explaining to me," he ground out, "why I found my wife - _my WIFE_ \- wrapped around my best friend on the sofa last night? Wearing bugger all? Hmm?"

"Nothing happened. At least  nothing of that sort." Sherlock was quick to add.

"He's right, dear. Nothing happened - other than a good night's sleep."

"Then why on  _earth_  were you  _naked?_ Or are you going to tell me that's normal now, too?"

"Don't be silly, we weren't naked!" Mary pointed out. "We kept on our underwear."

John had the distinct sensation of losing his grip entirely on reality. 

"But, but - what? What is that meant to prove? Am I the only one in this godforsaken house who thinks this is in any way a problem?"

John's voice was rising apace. Mary knew he'd soon be shouting and she was eager not to let it get that far. Once John let his anger out, it was hard to reel back in. Best nip this in the bud. She put her hand over his clenched left fist, tenderly. A reminder of all they had, all they were. Her other hand slid to Sherlock's larger one, resting on the table.

"John," she said. "I need you to listen very carefully. And I need you not to react until you've heard the whole of it. Alright?"

John found breathing increasingly difficult, but he nodded to Mary to continue.

"I've known for a long time - since the start actually - that you cared more for Sherlock than you ever cared to admit - no, let me finish," she said, seeing John's usual denial about to burst from the angry line of his lips. 

"I know it. You know it too. The only one who didn't know - was Sherlock. But now he knows it too."

She paused, watching John carefully. Choosing her words. Sherlock's eyes were also on John, but his were filled not with caution but with trepidation, perhaps with fear. 

"And darling, this shouldn't be a surprise, but I know it probably will be. Sherlock, he feels the same way, too."

Suddenly there wasn't enough air. John was gasping for breath. Some dim part of his brain knew he was just hyperventilating. But his body begged to differ, it was sure this was the end. 

"Breathe, my love," his wife was murmuring. "Breathe for me. There we go."

It was some time before she could resume, and even then, John couldn't even look in Sherlock's direction. This couldn't be happening. It couldn't be real. He wanted to be anywhere but here, right now, listening to his wife - his bloody WIFE - uncover his hidden heart. 

"You know that was why I brought out that stupid hat. I hoped - but never mind, that's not relevant any more. The point is - you love him. You'll always love him. And I love you."

John went to protest, to gesture, to do  _something_ , anything, but Mary waved him back. 

"Don't," she said simply. "Don't lie about this. It's too important. I know you love me too, perhaps not in the same way. But enough."

John stared back at the two pairs of eyes watching him, filled with such hope, such despair. He should say something. He wanted to say something. Why wasn't his mouth working anymore?

"What Mary is trying to say, John," said Sherlock, "is that - well - we both love you. We both want you. Neither of us is willing to let you go."

"What?" John's voice cracked on the single word. He felt like his mouth was full of cotton. His throat was dry. 

"Oh love," Mary said, with such tenderness in her voice. "we were never  _ordinary._ Don't try to be what you're not. None of us are. Think. Really think about it. What. Do. You. Want?"

"I - I don't  _know,_ Mary," he cried out, his voice so forlorn in the tiny kitchen. 

"Well," Sherlock's voice was dry as a dessert wind. "I think we have a suggestion in that regard."

John just looked at him, mouth hanging open. He couldn't process what was happening. He heard the words - but - they didn't make any sense!

Mary looked at Sherlock. Something clicked in his eyes, and he nodded, once. Mary smiled. The time for words had passed. Slowly, she leaned towards John and pressed her lips to his in a softly sensual kiss. Turning her head she shifted over and kissed Sherlock in the same deliberate way. She felt the sharp puff of John's breath on her cheek as he gasped, watching. He seemed half fascinated, half repulsed. Breaking the kiss, she took John's chin in her hand and turned his head so he was facing Sherlock. Barely a single second had passed before the detective's lips attached themselves to John's. 

_Oh my God. I am kissing Sherlock Holmes._

 

 

 


	8. Not Just Black or White

**Summary for the Chapter:**

> All three reflect on the kiss and what it means in their relationship(s)

_John, he was - finally - kissing John!_

Oh it was like Christmas and a locked room murder all at once. Sherlock's heart couldn't seem to beat fast enough. John's lips were - there were no words. This feeling had no words. And then - oh, Sherlock's stomach took a lovely swoop.  _John was kissing back._

_**_

_He was kissing Sherlock Holmes... how could he be kissing Sherlock Holmes? Sherlock wasn't like that._

John froze in a moment of stunned disbelief before his heart caught up with his thoughts and the bottom dropped out of his world. Unless he had somehow been drugged (and he never completely discounted that possibility) the evidence pointed to one amazing fact. Yes, he was indeed kissing - being kissed by - his brilliant and wow! probably not asexual after all - best friend. He wasted no further time. He took Sherlock's face in his hands and leaned into the kiss. Sherlock's lips were so soft, just as he'd imagined. He had to - oh God, he had to - use his tongue. He had no idea if Sherlock would allow it but he had to try. And then he was licking his way into Sherlock's mouth and Sherlock - Sherlock was not pulling back, he was - he was opening his lips, hungrily taking John's tongue into his mouth as both men lost themselves in this, their first ever kiss. 

 **

Mary was a solid presence behind John, one hand on his shoulder - ready to intervene if he spooked. She saw him tense, half afraid he would withdraw, before something, some walled-up piece of him, finally broke. All the longing he had been hiding came tumbling out and straight into this heady kiss. She felt privileged to be part of it. The need, the raw need, built up over years, was stunning to watch. She had never been the jealous type, but even so, had wondered if she'd really be able to do this, sharing John. But watching them felt right, as if part of a missing equation had fallen into place. The pulsing warmth spreading deep within her pelvis told her that this was something she would not just endure, but enjoy. 

**

The kiss seemed to both go on forever and be over way too soon. John surfaced first, drawn back by the steady pressure of Mary's hand on his back.  _Oh God, Mary._ But when he pulled back, twisting to look at her over his shoulder, he saw only warmth and acceptance in her face. He loved her. He did love her. But she was right, it was a different love than for Sherlock. That mad, intense, driven kind of love that consumed whatever it met. His love for Mary was a gentle thing, warming his heart in the face of a howling wind of loss. Steady and slow. He would never  _burn_ for Mary. But that didn't mean his feelings for her did not also run deep. And then suddenly he was overcome with gratitude for his wife, for her ability to see what he would not see and to accept what he could not accept. He was humbled and amazed that she had found it in herself to do this. To give him what she knew he both desired and - he could admit it now - needed more than air. With a sudden intake of breath he realised exactly what she was offering.  _He didn't have to choose._  

**

A cold spike of alarm shot through Sherlock's consciousness, jerking him back from a full, warm feeling of bliss. John was moving his wonderful lips away. The kiss was ending. _Why was it ending? Had he done it wrong?_ He wanted more. He had to have those lips again. He opened his eyes. John - his beautiful John - was looking at Mary, awe in his eyes. Sherlock could live with awe. It was better than panic, better than regret. He hoped John wouldn't regret it, wouldn't succumb to the ridiculously binary codes of right and wrong that underpinned everyday morality. This was - they were so much more than that. To have had this one, perfect kiss and then to have it taken away - _no, no he couldn't allow it, wouldn't -_

John's hand, warm and solid on his, halted the horrible panic that had been rising in Sherlock's gut. Sherlock lifted his eyes and met John's gaze - so tender and full of something Sherlock couldn't name. How could he? He'd never seen it before. He swallowed uselessly against the lump building in his throat. 

Mary's hand joined John's on top of his. Sherlock's intense focus narrowed to the picture their three hands made, resting in solidarity on the kitchen table. He shuddered under the weight of this, his feelings threatening to overwhelm him. After so long, so many misunderstandings, so much despair, he finally had hope. It was almost too much. He wasn't sure he could handle it. But he wasn't going to stop. Not for anything. John's hand tightened on his. He took a breath. He was so happy. Why was he crying? John would think he was sad. He wasn't sad. He _wasn't._      

 **

John could feel the exact moment Sherlock started to panic. He put his hand on Sherlock's, wanting to stop the feeling before it could grow. He knew that Sherlock wasn't used to  _sentiment._  And he knew that this, whatever this was, would be overwhelming. He hoped Sherlock hadn't changed his mind - God he hoped. But then Sherlock dipped his head and stared at their joined hands - Mary's on top of his and Sherlock's - with all the focus normally reserved for diseased livers or particularly noxious moulds. John could literally see him processing. He tried to push every ounce of his feeling for Sherlock down through his hand and across the thin barrier of skin. Sherlock just had to know how John felt. How could he not know. And then suddenly there were tears and Sherlock was -  _Jesus was Sherlock crying?_ \- and John couldn't bear it any more. He was around the table in two seconds flat and had wrapped his arms around Sherlock's trembling form. 

"It's alright, Sherlock. It's alright."

He pressed his lips to the top of Sherlock's head and was relieved to feel the man relax into his arms. He felt Mary's arms slip around him from behind. All of a sudden he knew with absolute certainty that everything was going to be ok. He didn't need to understand it or know its name. He and Mary and Sherlock would find a way to make this work. Because they had to. Because they could. He almost wanted to laugh at how easy it was, in the end. After all the agonising and wondering and soul-searching - in the end all it took was this. All it took was letting go. 

When he felt Sherlock had calmed down enough, he gave a squeeze and stepped away. 

"Tea?" he asked, nonchalantly. 

And he went to put on the kettle, barely able to contain his joy. 

 

**Notes for the Chapter:**

> Just wanted to thank people for hanging in despite short chapters and irregular (slow) updates. It may take a while but I promise this is not an abandoned fic!


	9. Building a Head of Steam

**Summary for the Chapter:**

> John, Sherlock and Mary agree some rules and start to get comfortable with each other - in preparation for their 'first time'.

They took their tea in the sitting room, all three piled on the oversize sofa. John found that now he had permission to touch Sherlock, he simply couldn't stop. They were not especially sensual touches, he just felt as if he couldn't bear for some part of him not to be in contact with some part of Sherlock at all times. It felt a little unreal. Perhaps the touches were his attempt to prove to himself that this was actually happening, not some mad fantasy playing out in his sleep-deprived brain. 

As for Sherlock, he could barely keep the grin off his face, John had never seen him look so happy. His touches in return were tentative little things - but they were there. That is all that mattered. 

"I think - I think we should take this very slowly," he said, blowing across the top of his mug of tea. 

"Yes, there's no rush. It'll take time to get used to this, to how this works, between us," Mary replied. 

"Do you think - I mean, are we going to, you know - " John was stuttering, he didn't know how to put this, really. Well, it was rather an unusual situation. 

"Do get to the point, John," snapped Sherlock, but it was entirely without venom, so John knew it was just for form's sake really. 

"Alright," he took a steadying breath. "What I'm trying to ask is how will this work? Is this a purely platonic thing, just - you know - cuddling and stuff? Which is fine, by the way. If that's what you want."

He broke off, looking at Sherlock, who gazed back steadily before he placed his hand, deliberately, on John's upper thigh and opened his mouth - his beautiful mouth - to reply. 

"Not. Platonic."

John shivered.

"Oh, thank God," he said.

"You have questions," Sherlock said, eyes still locked on John's.

"I - yeah, I guess I do. Like - I presume that means sleeping together. You know. Sex."

He took a shuddering breath before continuing.

"So will it be all three of us at the same time? Or separately? And if so, will you two, you know, together too? I mean - I don't even know how that would work - do you even _like_ women, Sherlock? Do we need some kind of weird scheduling system?"

His voice was rising again, not quite in panic, but speeding up, as if his words couldn't quite keep up with his thoughts.

"It's a lot to get your head around, darling," Mary said. "We've had a little longer to think about the details." 

"What we thought," Sherlock interjected, "was that it should be all three of us. Together. At least to start with. And to answer your question, I do have experience with both men and women so - well, it won't be a problem. And I like Mary, I really do. And she likes me."

"And we both love you," Mary added. 

"Problem?" Sherlock asked, his head tilting in such a typical way that John's heart just melted. Even if he'd had any objections - and he didn't, by God, he didn't - that would have clinched it for him. 

"No. Not a one," he replied, a genuinely happy smile blooming on his face. 

They returned to their tea, each lost in thought. Eventually Sherlock cleared his throat, catching Mary's and John's attention. 

"Jooohn," he said, his voice low and deep and achingly seductive, his eyes so wickedly dark. "When you said  _slow_ \- just how slow did you mean, precisely?" 

Beside him, Mary sniggered while John - who wasn't sure what he was expecting, but certainly not _that -_  almost choked on his tea. 

 ***

John, always the sensible one, insisted they wait a little before, as he called it, 'jumping in'. He felt he needed just a little time to get used to the idea. He also insisted they all get tested and made Sherlock and Mary both promise that they would not engage in unsafe activities in the outside world. 

"I mean it Sherlock," he said. "No iv drugs, no casual sex, and  _definitely_ no putting your hands in corpses or puddles of blood or other bodily fluids at crime scenes unless you're wearing  _gloves._ "

"I promise, John," Sherlock said. He meant it too. "I would never put you or Mary - or the baby - at risk that way. It's - well, it's not just about me any more, is it?"

Deep down Sherlock worried sometimes about what would happen when baby Watson arrived. He couldn't quite see how this arrangement would continue to work once John and Mary became Mom and Dad. But - he put the thought firmly aside and decided to take whatever he could get of John.There was no way he was going to miss out on this, the opportunity of a lifetime, to be with - really with - the man he loved. He would store it away in his mind palace against the day that they changed their minds, that 'we' became once more 'not-you'. He could only hope the memories would be enough to help him weather the storm. 

In the meantime, they had several blissful days of lounging about and just  _touching_ each other, in the most gentle and loving of ways. And kissing, lots and lots of kissing. Long intense sessions of making out like teenagers, sprawled over and under and around each other like puppies. It was heaven. It was connecting. It was just what everyone needed. 

By the end of the week, however, Sherlock had been reduced to a squirming mess. He hadn't been touched in so long, never mind snogged to within an inch of his life. His penis, unused to this kind of stimulation, reacted most alarmingly. He was actually glad he had no cases on, he could hardly walk straight with the damn thing perpetually hard, it was downright embarrassing. He hadn't resorted to masturbation quite yet - but it was a close run thing. He couldn't take much more of this. Something, clearly, had to be done. 

***

 


	10. Beginnings

**Summary for the Chapter:**

> In which plots are plotted and moves are made

Sherlock was nothing if not creative. He paused briefly at the door to the sitting room, hair beguilingly tousled from the shower and skin a fetching shade of pink (he'd had to turn the water up quite hot but it was so worth it) _._ He steadied himself and took a deep breath, glad that Mary kept the heat a constant 20 degrees these days - she was always cold. Desperate times called for desperate measures. He cocked his head at a regal angle and swanned into the room. Three steps in, he let go of his grip on the towel. 

John's gasp was a thing of beauty, and Mary, bless her, smirked. 

But Sherlock had reckoned without John Watson's infamous stubborn streak. The man strode from the room, returning almost immediately with Sherlock's favourite blue dressing gown. 

"No, Sherlock. Taking it slow. Remember?"

Sherlock sighed. He put on his dressing gown. And went back to the drawing board. 

***

Three days and several foiled plots later he was ready to admit defeat. No amount of pouting, groping, posturing or dressing provocatively seemed to work.  Time for a more direct approach.

"John, Mary," he said. "Come to the kitchen, I have something I need you to do."

Mary arrived first, and predictably found the sight before her rather amusing.

"Oh, Sherlock," she giggled. "Aren't you the eager one!"

John, hot on her heels, baulked at the row of carefully placed needles and vials on the counter.

"Don't worry," Sherlock said, in his most reassuring rumble (he had noticed by now the effect his voice had on a certain blogging doctor). "They're properly sterile."

"Sherlock?" The warning in John's voice was hard to miss. "What exactly are you planning on doing with those?"

"A blood draw, of course. And you'll have to, umm, you know, pee in this," he said, waving a plastic jar.

"I've asked Mycroft to put a rush on the tests. He knows people."

At least His Royal Smugness could be useful for  _something_ , even if he would undoubtedly look as if he had encountered a particularly bad smell when he heard the request. Serve the insufferable git right, he thought, to be made uncomfortable now, having been the recipient of rather too-much information for most of Sherlock's adult life. God knew he stuck his nose in where it wasn't wanted often enough. What was that phrase John used? Something about chickens and roosting?

Mycroft did exactly as Sherlock asked, and tried not to think about the implications along the way. He put in a call to a discrete and very helpful clinic he knew of. One could never have enough contacts when one's brother was a certain Sherlock Holmes. Though God knew he hadn't expected to be asked to perform this particular task on behalf of his little brother. Or the married couple in whose house he was currently residing. He shuddered faintly and resolved to simply put it out of his mind. 

Twenty four hours later the results were emailed through. All clear. (The 'Of Course' that was implied in the rolled eyes went without saying).

Sherlock had spent the day pacing, barely restraining the sense of eager anticipation. By the time evening fell, John had been forced to tackle him to the sofa and snog him senseless before the idiot did himself some damage. Or wound himself up so far that he would push over the edge into manic - and that would defeat the purpose entirely, he was sure.

Now that the path had been cleared, however, Sherlock found himself unaccountably nervous. He swallowed, mouth suddenly dry. Oh God, what if he couldn't do this? What if he was terrible at it? What if he had a panic attack? What if - 

"Stop!" John commanded - and wasn't that a turn-on, that Captain's voice turned on him in all its intensity. But how had he known what Sherlock was thinking in the first place?

"It's written all over your face," John helpfully supplied. "I can see you're panicking. So just stop it Sherlock, there's no point in winding yourself up about this. We don't have to  _do_ anything. Certainly nothing you're uncomfortable with."

"But what if I - if I disappoint you?" he whispered. 

"Oh Sherlock," John's hand stroked the detective's cheek so gently it made him want to cry. "There's nothing - literally nothing - you could do that would disappoint me. Except to get all upset about this when there's no need. I'm already crazy about you. Nothing will change that. I'll always love you, you mad, brilliant thing you. Just relax. Let this happen. Or not. It's all the same. No rush. No pressure. Whatever you want, love. Whatever you need."

John's words went a fair way to reassuring the anxiety buzzing low in Sherlock's belly. He took a breath, then another, and let it out again. He could do this. It was going to be fine. 

***

That night, Mary directed John to build a fire in the den and Sherlock to fetch the duvet and double mattress from the spare room. She gathered linens and pillows and set about making a 'nest'. Might as well be comfortable. She served each man a tumbler of whiskey, sticking with water for herself. She reckoned they'd need something to take the edge off - but not enough to be impaired. She wouldn't want to waste this opportunity, after all the work it took to get them here.

A small part of her could barely believe her plan had worked. If all went well tonight, they'd all get what they wanted. She was under no illusions that this first evening would mostly be about John and Sherlock finally taking that step. But in all honesty, heavily pregnant, it's not like she'd be up for anything terribly energetic anyway. No, she'd be happy just to be included, able to share in the reflected glow. And if it meant John's hands, John's mouth, on her again - well, she was only human. She certainly wouldn't say no. 

***

Finally everything was ready. No more procrastinating. Sherlock's mouth was dry and his heart was pounding so hard he was sure it was about to leap out of his chest. But from the look on John's face he knew he wasn't the only one to find this - uncomfortable. There was a moment of tension - and then John, lovely John, reached out and took his hand, pulling their bodies together. This, he was used to. This he could do. Their lips met, soft and full, for a long and teasing kiss. Mary settled herself comfortably against the arm of the sofa, enjoying the view. 

The kiss rapidly turned heated. Frantic hands fumbled with buttons and fastenings and clothes were abandoned wherever they lay. John deepened the kiss, delighting in Sherlock's sinful little moan. And suddenly they were naked and - oh, all that wonderfully tanned skin was pressed right up against Sherlock's pale chest and he could hardly contain himself any more. Little brushes of skin on skin set trails of fire running up his spine. He lowered himself to the mattress, pulling John behind him. It felt like heaven. He shivered when John shifted and their cocks - God, so hard - came into contact.  He really wasn't going to last long. He heard Mary shifting behind them and glanced around at her, meeting her eyes, noting how flushed she was, breathing almost as heavily as the two men. Seeing her hand moving slowly beneath the fabric of her knickers sent an unexpected dart of lust through him. The thought of her watching them, getting off watching them, how good they looked together, was enough to bring him to the brink.

John brought his hand between their heaving bodies, but his hand was too small to reach all the way properly around both erections, so Sherlock, desperate to come now, wrapped his long, elegant fingers around John's and started a punishing pace of stroking, just a little too dry - but oh, the friction was a thing of beauty. John's whispered "Jesus" was possibly the most erotic thing he'd ever heard. He felt the heat mount and mount until he almost couldn't bear it any more. Mary's fingers matched theirs in a frantic rhythm. He felt it peak, and crest, and he couldn't help crying out in pure joy as he orgasmed hard, spilling copiously over both their hands. Seconds later, John - with the most wonderful groan - added his own fluids to the mess and Sherlock felt rather than heard Mary stiffen and jerk as she too found her release. 

Later, as they lounged on the mattress, naked and sated, Sherlock would privately wonder if this wasn't, after all, the best bit. But he wouldn't let on, he thought, as he kissed his soldier languidly and slid a large hand slowly down Mary's flank in gratitude.  No, he had a reputation to uphold. Wouldn't do to be seen enjoying the cuddling. It didn't really matter, John and Mary would know anyway. They knew him better than anyone, after all. He found it harder than it should have been to mask his joyous smile as he settled in for the night. Never mind if he slept or not, wild horses or even a locked room murder wouldn't drag him away from the nest tonight. No, he had everything he ever wanted. No way was he letting go. 


	11. Sleeping Arrangements

**Summary for the Chapter:**

> Sherlock waits for the other shoe to drop.

Sherlock was first to surface the next day. He wallowed a bit in the press of naked flesh on either side, eyes screwed shut against the soft morning light. Surprisingly, he found he didn't particularly care whose skin was pressing where. It was all good. All fine. And so deliciously warm. He sighed in contentment and settled down for a prolonged bout of  _snuggling._  Who knew something so average, so mundane, could feel so delightful!

 

He must have dozed off again, because when he next woke, the space on his right was empty. From the kitchen he could hear the unmistakable sounds of John Watson's morning puttering with the tea. He smiled. It sounded just like home. Beside him, Mary stirred, slowly coming awake and he tensed slightly, waiting for her reaction in the cold light of a newly minted day. 

"G'Morning," she slurred, stretching. 

"It is, isn't it? Good?"

His words made way for a soft, hopeful smile. He found himself pleased beyond measure to find that Mary's answering smile held not a hint of regret. 

 

John came clattering into the room carrying a tray which held three mugs of tea and a frankly ridiculous amount of hot buttered toast.

"Morning my lovelies."

He looked like his face would split open from the sheer force of his smile. Sherlock's heart gave a jump. No regret there either. Two for two. He almost couldn't believe his luck! Deep down he had been sure they would come to their senses and announce that last night had been a mistake. 

Perhaps sensing the direction his thoughts had taken, Mary reached for Sherlock's hand and gave it a squeeze. 

"Come on then," she said, "give us a hand up. This pregnant person needs to pee."

With Sherlock half-pushing and John pulling in counterweight from the other side, she worked her way slowly to her feet. John moved the tray to the coffee table, then wriggled his way gleefully back under the duvet. He rolled onto his side and looked at Sherlock, who was suddenly, unaccountably shy. The two men looked at each other for a minute. John was the first to move his head slowly, carefully, towards Sherlock's until finally their lips were touching in a soft and tender kiss. 

 _I could get used to this_ , Sherlock thought, as John pulled his lips back again with a soft hum, before he leaned over and grabbed his mug of tea. 

***

_I believe congratulations are in order, little brother. MH._

_**Sod off Mycroft! SH** _

Sherlock sighed. Nothing, it seemed, was beyond the interest of the British Government. He made a mental note to do a sweep for hidden cameras in the Watsons' house again. Not that he'd mention it to the Watsons. He wondered which of Mycroft's minions had received an eyeful last night. Then he wondered how he might get his hands on a copy of the tape?

***

In the spirit of military efficiency, John tidied away the bedding before he left for the surgery. His eyes lingered on the impromptu 'nest' before dismantling it, and he found it hard to restrain a smile at the associations. Lovely as the night had been, though, they would need to make arrangements for something more permanent than a mattress slung on the floor, especially with Mary being so awkward on her feet at the minute. He'd talk to Mary later - she'd gone back to bed for a proper rest, so he wouldn't disturb her now. He called a quick goodbye to Sherlock, who was wallowing noisily in the bath tub and not likely to leave it any time soon. He tried not to dwell on the sounds of water splashing over those acres of lean muscle, or he'd never make it to work. 

On the way to the tube station he pulled out his phone and googled 'king size beds'.  He made a mental note to measure the space available in the master bedroom. After all, they were going to need a bigger bed - or at least, he fervently hoped so! John spent rather a lot of time in between patients thinking about beds in general and their suitability for various - ahem - activities. He wondered if they'd need a reinforced base? _Christ, who could you ask about things like that? Was there some website, pollyamory.com, that gave advice on the practicalities of this kind of , well, arrangement?_ It was not something he'd ever had to worry about before. Not that he was complaining, mind. Not at all. But he had never expected himself to be in this position, at this stage of his life, married and with a baby on the way. 

Most of his lunch hour was spent pondering some vital questions. Like who'd get to be in the middle. Maybe they'd rotate? Or would Sherlock prefer not to always be beside Mary? She'd probably need an edge slot, what with the baby pressing on her bladder at inopportune moments. As for him, well, normally he liked his space - but he was quite sure he wouldn't mind being hemmed in given the circumstances. 

He sent a few bed store bookmarks to Mary and received a winking smiley in return. Good, she was on board then. He'd talk to Sherlock this evening over dinner, see if he had any special requirements to add. 

And if the good doctor seemed a little distracted at work today, and a little too eager to leave that evening - well, who would blame him? The other doctors put it down to the joys of imminent fatherhood and cut him a little slack. The man hadn't stopped smiling like a lunatic all day.

*** 

"Hey there. Where's Sherlock?" he asked Mary, as soon as he'd hung up his jacket. 

"In his room I think, haven't seen him all day. I figured he might be in need of some quality mind-palace time, after all the excitement yesterday."

She smirked, her dimple showing, at the thought. 

"I'll give him a shout, I got takeaway for dinner."

John trotted up the stairs and knocked gently on Sherlock's door. 

"Sherlock? Thai for dinner. Coming down?"

No sound save a rather ominous silence. He tried again.

"Sherlock? You in there?"

"Go away, John."

"What?"

"You heard me. Leave me be."

John's heart sank. Oh God, he'd hoped - he'd really hoped - that Sherlock would be happy to see him. Things were panning out a little differently than he'd been imagining all day.

"Alright then," he sighed, before turning and walking slowly back down the stairs. 

Mary read the concern in John's face before he even opened his mouth.  

"What's wrong?" she asked. 

 "Sherlock seems to be in a bit of a strop in his room, as far as I can tell. Hope he's not regretting, well, you know." 

 Mary rolled her eyes. 

"You mean you didn't check on him? Make him tell you what's going on in that genius brain of his?"

"Errr. No."

John watched as his wife moved towards Sherlock's door, muttering darkly about 'emotional constipation'. He was pretty sure he caught the word 'idiots' in there as well. 

***

 "Sherlock?" Mary's voice was soft as she tapped on his bedroom door. "Can I come in?"

The answering grunt could mean anything or nothing, but she chose to take it as permission all the same. She edged into the room and closed the door quietly behind her. Sherlock was curled on his side, glowering at her and hugging his own knees. 

"There you are," she muttered.

"Where else would I be?" he asked, sarcasm thick on his tongue. 

"John thinks you're having second thoughts," Mary said. Well, she thought, no point in beating about the bush with these two. 

"John thinks  _I'm_ having second thoughts?  _I'm -_ he's the one who was so eager to pack up the bedding!"

" _That's_ what this is about? Because he put away the blankets?"

Sherlock's mumble was impossible to make out. 

"Sorry, Sherlock, what was that you said?"

"I said, he made it quite obvious where I fit into the equation. You two have your room, I have mine. The natural order has been restored. I didn't realise it was meant to be a once off, that's all. It's fine."

"Oh Sherlock!"

"Don't, Mary. It's hateful. Just don't." He cast one arm over his brow, hiding his face from view. 

Mary knew when to pick her battles. This was time to beat a strategic retreat. She'd go talk to John and see if they couldn't find a way to reassure their - because, yes, he was theirs now - miserably insecure detective that he belonged.


	12. Dare to believe

**Summary for the Chapter:**

> Mary and John tag-team to help Sherlock understand his new role.

"What do you mean, he thinks he doesn't belong? After last night - how? How can he think that?"

"Oh love, he's feeling a bit insecure. He's Sherlock bloody Holmes for Christ's sake. Of course he's over-thinking it. When you moved the mattress he assumed the worst, that you'd changed your mind without saying so." 

"But that makes no sense!"

"I know, but look at it from his point of view. You and I share a bed. He's in the guest room. Moving the mattress means he's back to sleeping there. Presumably alone."

"Oh. Oh I see. Well he's wrong. Dead wrong."

"Well I know that - but he isn't listening at the moment."

"What should I do?"

"Oh - I might just have an idea or two..."

***

John balanced his tray on a side table and rapped a loud staccato on Sherlock's door. He didn't wait for a response before he shouldered his way into the room. Sherlock scowled up at him from a tangled sprawl of limbs - but at least he didn't shout at John to leave. His eyes looked - vulnerable, in a way that hurt John almost physically.

John wrangled the tray in to the room and planted it on the nightstand.

"What are you doing?" spat Sherlock.

John just hummed.

"Bringing dinner," he said, lifting a cardboard box and handing it to a rather nonplussed Sherlock.

John sat on the bed, lifting his legs and leaning on the headboard. He lifted a second box and fork and calmly started to eat.

"It's good. Try it."

"John - what -"

"Seriously. You need to try this, Sherlock - here."

A forkful of Pad Thai hovered resolutely in front of Sherlock's mouth until he gave in and opened wide.

The detective shot him a dark glare but continued to eat in silence for a while, chewing thoughtfully. 

"Where's Mary?" he asked, eventually, when it seemed clear that John wasn't going to say anything so long as there was food to be had. 

"Having a long bath and catching up with her latest spy novel," John chuckled at the irony of a trained assassin enjoying books about spying. He reckoned she only read them to pick out the mistakes. 

"And then she's taking an early night," he continued. "She said she's tired, well that happens a lot in the last trimester. She'll come join us in the morning. If we're lucky, she might even bring us some tea."

Sherlock stared at John, a thousand questions stuck in his throat. John rolled his eyes, removed the takeaway box from Sherlock's grasp and deposited it with his own on the tray. 

"Come here you great git," he said, wrapping his best friend (and now lover, too) in  his arms. Sherlock squawked a token protest but John could tell it was only for form's sake.

"I missed you today. I couldn't stop thinking about you." 

"Really?"

The uncertainty in Sherlock's voice stung. _Honestly_ , John thought, _how could he not know_?

"Yeah. I even got to do some research - in between patients."

"What kind of research?" 

Ah. He had him now!

"Practicalities, really. Like where to get a big enough bed for three people to fit comfortably. I reckon we may have to have one specially made. And it'd have to be sturdy. You know. For all the _action_ it's going to see."

John could barely contain his grin at the sweeping blush engulfing Sherlock's skin, prompting the overwhelmed detective to bury his face in John's shoulder. He sagged against his soldier in relief as John's hands came up to tease whisper touches through his curls. 

"How could you think I wouldn't keep on wanting you? After everything?"

"Nobody's ever stayed before," came the anxious whisper.

"Sherlock Holmes, you're my best friend and I love you. I'm _never_ going to let you go."

John could tell the detective still harboured some doubts, but he was convinced enough to stay where he was and allow John to run his fingers over his scalp for a long, strangely intimate, moment. 

"Alright," John said, eventually. "Let's get ready for bed, then."

"You mean you're sleeping here? With me?"

John did his best to hide a grin at how adorable an insecure Sherlock could be. He met those pale eyes with his own, knowing that the other man would believe his affection for the great git more readily if he deduce it from the warmth of John's own smile.  

"Yes. If you'll have me. Just sleeping mind. I'm tired from running on adrenaline all day. But I rather fancy a cuddle. That ok?"

Sherlock had by now recovered sufficiently to roll his eyes before rumbling his reply.

"Of course, John. Don't be an imbecile."

John chuckled as he scrambled from the bed to grab some pyjamas and visit the loo. 

"Hurry up, then," he said. "Last one back's a rotten egg!"

Sherlock jumped up in a flurry of arms and legs. He always did respond well to challenge. And if John let him win, just a little, well, it was worth it to see the smug look of satisfaction crossing that beautiful face. John gave himself a moment to just soak in the alien features, before he tackled the man to the mattress and held on for all he was worth. Tight enough to prove even to Sherlock Holmes that he was most definitely loved.  

 

 

**Author's Note:**

> Given the way the Mary plot expanded in S4 I found I couldn't bring this any further along the path I'd originally intended. So.. having re-read it I figure the place it ended is as good as any. Maybe I'll come back to John/Mary/Sherlock again some day..


End file.
